1. Field of the Invention
The present invention relates to an ink fountain apparatus for a printing press, and more particularly to an ink fountain apparatus having an inclined member which can approach and separate from an ink fountain roller, and a mechanism for moving the inclined member.
2. Description of Related Art
In an ink fountain apparatus of an ink supply apparatus for a printing press, ink is stored in an elongated space which has a V-shaped cross section and which is formed by the peripheral surface of an ink fountain roller and an inclined member which includes an ink supply adjusting member having a forward edge located in proximity to the peripheral surface of the ink fountain roller, a pair of side plates disposed at both lateral ends of the ink supply adjusting member, and other members. When the ink fountain roller is rotated, the ink stored in the elongated space is withdrawn through a gap between the peripheral surface of the ink fountain roller and the forward edge of the ink supply adjusting member.
To control the supply of ink, the size of the ink supply outlet, i.e., the gap between the peripheral surface of the ink fountain roller and the forward edge of the ink supply adjusting member is adjusted by advancing and retracting the ink supply adjusting member.
When ink stored in the elongated space having a V-shaped cross section, i.e., in the ink fountain, is replaced or when ink remaining in the ink fountain after completion of printing is removed, the ink fountain apparatus must be washed, cleaned, and subjected to maintenance work.
To facilitate such work, a mechanism is provided to separate the inclined member, which forms the elongated space having a V-shaped cross section, from the ink fountain roller to form a large gap between the inclined member and the ink fountain roller, and to move the inclined member toward the ink fountain roller to return the inclined member to the original position.
Japanese Utility-Model Publication (kokoku) No. 36-6808, Japanese Patent Publication (kokoku) No. 3-63953, Japanese Utility-Model Publication (kokoku) No. 57-13253, Japanese Utility-Model Application Laid-Open No. (kokai) 4-9737 and U.S. Pat No. 4,123,972 disclose conventional mechanisms for moving the inclined member of an ink fountain apparatus.
In the mechanisms disclosed in these documents, means for moving the inclined member are provided under the inclined member. In the mechanisms disclosed in Japanese Utility-Model Publication No. 36-6808 and Japanese Patent Publication No. 3-63953, a toggle mechanism is used as the moving means. In the mechanism disclosed in Japanese Utility-Model Publication No. 57-13253, a link mechanism is used as the moving means. In the mechanism disclosed in U.S. Pat. No. 4,123,972, a worm mechanism is used as the moving means. These mechanisms serving as the moving means are all operated manually to cause the inclined member to approach and separate from the ink fountain roller.
In the mechanism disclosed in Japanese Utility-Model Application Laid-Open No. 4-9737, a hydraulic cylinder is used as the moving means. The piston rod of the hydraulic cylinder which is in direct contact with the inclined member is advanced and retracted to cause the inclined member to approach and separate from the ink fountain roller.
In the manual mechanisms disclosed in Japanese Utility-Model Publication No. 36-6808, Japanese Patent Publication No. 3-63953, Japanese Utility-Model Publication No. 57-13253 and U.S. Pat. No. 4,123,972, the work load of an operator increases when the weight of the inclined member increases, resulting in a decreased work efficiency.
In the mechanism disclosed in Japanese Utility-Model Application Laid-Open No. 4-9737, both lateral ends of the inclined member are pressed against stoppers by a large force produced by the hydraulic cylinder when the inclined member is stopped at a position where it forms an ink fountain after approaching the ink fountain roller. When the positions of the stoppers on which the inclined member abuts slightly differ from each other, the inclined member deforms due to the strong pressing force produced by the hydraulic cylinder. In this case, it becomes difficult to advance and retract the ink supply adjusting member toward and from the ink fountain roller so that the work for adjusting the gap between the forward edge of the ink supply adjusting member and the peripheral surface of the ink fountain roller becomes inconvenient.